Recording device

Abstract

To provide a recording device taking reliability on a recording head into consideration.SOLUTION: A recording device comprises: a first nozzle 310 provided in a liquid discharge part to oppose to a sheet; a second nozzle 210 provided in the liquid discharge part to oppose to the sheet and positioned at a downstream side in a moving direction of a carriage with respect to the first nozzle 310; and air flow generating means that generates air flow flowing in a conveying direction between the sheet and the liquid discharge part. Control means sets the magnitude of air flow generated by the air flow generating means on the basis of the moving speed of the carriage and arrangement of the first nozzle and the second nozzle.SELECTED DRAWING: Figure 12

Description

Technical Field

[0001] The present invention relates to a recording apparatus that performs recording by discharging a recording liquid such as ink, and more particularly to a recording apparatus configured to be capable of individually discharging a reaction liquid capable of aggregating a coloring material in the ink.

Background Art

[0002] In a recording apparatus such as an inkjet printer, when obtaining an image on a recording medium called so-called plain paper, the water resistance of the image may be insufficient, or it may be difficult to achieve both water resistance and an image without bleeding. To address such problems, in order to obtain a color image with good image fastness and good quality, a technique has been disclosed in which a reaction liquid capable of aggregating a coloring material in the ink is recorded at substantially the same position as the ink containing the coloring material on the recording medium (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a recording apparatus using a reaction liquid that reacts with recording ink, reaction fixing on the face surface of the recording head hinders the reliability and long life of the recording head, and a configuration for generating an air flow in the vicinity of the recording head to address this is known. Patent Document 1 discloses a recording apparatus configuration in which an air flow is generated in a direction intersecting the reciprocating movement direction of the carriage in a discharge area facing the recording medium support surface.

[0005] However, in the above example of Patent Document 1, in the region between the droplet ejection portion and the recording medium support surface in the ejection region, a shielding portion is provided that shields the airflow in a direction intersecting the reciprocating movement direction of the carriage. Therefore, there is a possibility that the reaction fixing on the recording head face cannot be effectively suppressed. On the other hand, if the airflow in the region between the droplet ejection portion and the recording medium support surface is too large, it may also have an adverse effect on the landing accuracy.

[0006] An object of the present invention is to provide a recording apparatus that takes into account the improvement of the reliability of a recording head.

Means for Solving the Problems

[0007] To achieve the above object, the recording apparatus of the present invention includes transport means for transporting a sheet in the transport direction, a carriage that performs reciprocating scanning in a crossing direction intersecting the transport direction, a recording head held by the carriage and having a liquid ejection portion for ejecting liquid onto the sheet, a first nozzle provided in the liquid ejection portion so as to face the sheet, a second nozzle provided in the liquid ejection portion so as to face the sheet and located on the downstream side in the moving direction of the carriage with respect to the first nozzle, airflow generating means for generating an airflow flowing in the transport direction between the sheet and the liquid ejection portion, control means for controlling the magnitude of the airflow generated by the airflow generating means and the moving speed of the carriage, and is a recording apparatus comprising wherein the control means sets the magnitude of the airflow generated by the airflow generating means based on the moving speed of the carriage, the distance between the first nozzle and the second nozzle in the moving direction, and the arrangement of the first nozzle and the second nozzle.

Effects of the Invention

[0008] According to the present invention, it is possible to provide a recording apparatus that takes into account the improvement of the reliability of a recording head.

Brief Description of the Drawings

[0009]

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Best Mode for Carrying Out the Invention

[0010] Hereinafter, with reference to the drawings, preferred embodiments of the present invention will be exemplarily described in detail. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described in the following embodiments should be appropriately changed according to the configuration and various conditions of the apparatus to which the present invention is applied. Therefore, unless otherwise specifically described, it is not intended to limit the scope of the present invention.

[0011] (Embodiment 1) [Configuration of Inkjet Printer] FIG. 1 is a schematic cross-sectional view showing the overall configuration of an inkjet printer (printing apparatus) according to an embodiment of the present invention.

[0012] The printing apparatus 100 is a recording apparatus that ejects ink as a recording liquid from an inkjet print head (liquid ejection head) onto a sheet 101 as a recording medium to record (print) an image (including characters, symbols, etc.). The printing apparatus 100 includes a printing unit 107 that performs printing. The printing apparatus 100 further includes, in the printing operation A blower mechanism unit 120 is provided to flow the mist-like ink mist (sometimes simply referred to as mist) generated between the print head 105 of the print unit 107 and the sheet 101 to the downstream side in the sub-scanning direction (X direction). This blower mechanism unit 120 is a characteristic feature of the present invention as an airflow generating means, and its details will be described later.

[0013] The print unit (recording unit) 107 has a carriage 106 and a print head (recording head) 105, and the print head 105 is mounted and held on the carriage 106. The print head 105 is provided with an inkjet energy generating element such as a heating element or a piezo element, and performs recording by discharging ink from the discharge port (nozzle).

[0014] The carriage 106 reciprocates in the main scanning direction (the intersecting direction intersecting the conveyance direction of the sheet 101) along the guide rail 112. Further, the printing apparatus 100 includes a platen 108 that supports the sheet 101, which is a recording medium, facing the print unit 107, and a pair of conveyance rollers 130 that convey the sheet 101. The pair of conveyance rollers 130 includes a conveyance roller 104 and a pinch roller 103 that is driven by the conveyance roller 104. A roll in which a continuous sheet is wound in a roll shape is set in the paper feeding unit 131, and the sheet 101 unwound therefrom is conveyed by the pair of conveyance rollers 130.

[0015] In the printing operation, an operation of discharging ink onto the sheet 101 while moving the print head 105 in the main scanning direction (Y direction) by the carriage 106 and an operation of step-feeding the sheet 101 in the sub-scanning direction (X direction) are repeated to form an image. Such a printing apparatus 100 of a serial printing method further includes an operation panel 102, a cutter 110, and a storage basket 111. The continuous sheet is cut by the cutter 110 every time one image is printed and discharged into the storage basket 111.

[0016] [Configuration of the main part of the apparatus] Referring to FIG. 2, the configuration of the main part of the apparatus will be described in more detail. FIG. 2(a) is a schematic perspective view of the printing unit and the blower mechanism unit, and FIG. 2(b) is a schematic cross-sectional view of the printing unit and the blower mechanism unit. In FIG. 2(a), for the sake of clearly showing the apparatus configuration, some illustrations of the configuration shown in FIG. 2(b) are omitted.

[0017] The printing apparatus 100 includes a chassis 113 at a position facing the printing unit 107. The chassis 113 is a stay that supports the platen 108, the pinch roller 103, and the conveyance roller 104. Further, the printing apparatus 100 includes a main stay 114 at a position upstream of the chassis 113 in the sheet conveyance direction. A rail stay 115 and an exterior stay 116 are attached to the main stay 114. A guide rail 112 on which the carriage 106 travels is supported by the rail stay 115. An exterior cover 117 of the apparatus is attached to the exterior stay 116, and this exterior cover 117 can be opened and closed with respect to the exterior stay 116 for internal maintenance of the blower mechanism unit 120 and the printing unit 107.

[0018] [Configuration of Blower Mechanism Unit] Hereinafter, the blower mechanism unit 120 that is a feature of the present invention will be described. The blower mechanism unit 120 includes a blower duct 109, and the mist-like ink mist generated with the discharge of ink from the print head 105 is flowed downstream in the sub-scanning direction (X direction) by the air blown from this blower mechanism unit 120. The air outlet 109a of the blower duct 109 is located upstream of the print head 105 in the sheet conveyance direction. Since this is close to the source of the ink mist, an effect of efficiently flowing the mist is expected.

[0019] FIG. 3 is a schematic cross-sectional view showing the structure of the fan unit 119. The fan unit 11 9 forms the core of the blower mechanism section 120 and is fixed to the upstream end of the air passage of the blower duct 109. The fan unit 119 includes a fan 123 and a rectangular parallelepiped fan housing 124 that houses the fan 123. The fan housing 124 is provided with an air outlet 129 on its side surface and an air inlet 121 on its bottom surface. The fan 123 can be rotated, stopped, and its rotation speed changed by electrical control of a motor (not shown). When the fan unit 119 is driven, the airflow blown out from the air outlet 129 passes through the blower duct 109 and is wiped out from the air outlet 109a of the blower duct 109. The blower mechanism section 120 is configured to be able to control the magnitude of the airflow discharged from the air outlet 109a by controlling the magnitude of the rotation speed of the fan 123.

[0020] [Configuration of the recovery section] FIG. 4 is a schematic plan view showing the configuration of the recovery unit 70. The printing apparatus 100 of the present embodiment includes a recovery area by the recovery unit 70 in a non-recording area outside the conveyance area (liquid discharge area by the print unit 107) of the sheet 100 in the moving direction of the carriage 106. The recovery unit 70 has a preliminary discharge receiver 71 and a wiping mechanism 72. The preliminary discharge receiver 71 is configured to be able to receive ink or the like discharged by the preliminary discharge of the print head 105 in the non-recording area. This preliminary discharge operation is performed to recover the performance of the nozzles, such as removing ink residues in the nozzles from the nozzles. The wiping mechanism 72 includes a wiper that can wipe the liquid discharge section that contacts the liquid discharge surface (face surface) including the nozzles of the print head 105 and wipes off the ink from the liquid discharge surface by relative movement as a wiping means. The recovery area is also called the home position, and during the intervals between recording operations, the print head 105 is moved to the recovery area to perform recovery by preliminary discharge and wiping regularly. For example, in the present embodiment, the preliminary discharge during recording is performed every two scans, and the wiping is performed every 20 scans. As shown in FIG. 4, in the present embodiment, the wiping is performed in a direction orthogonal to the carriage scanning direction to clean the ink or the like adhering to the print head 105.

[0021] [Recording Control] FIG. 5 is a diagram showing the configuration of the recording control system in the printing apparatus of the present embodiment. The control unit 10 includes a CPU 401, a ROM 402, a RAM 403, an interface 404, an image processing unit 405, a head control unit 406, an engine control unit 407, a carriage control unit 409, a blower control unit 410, a recovery control unit 411, and an operation unit 412.

[0022] The CPU (Central Processing Unit) 401 integrally controls the operations of the respective units of the printing apparatus 100. The ROM 402 stores programs for the CPU 401 to execute and fixed data necessary for various operations of the printing apparatus. The RAM 403 is used as a work area for the CPU 401, as a temporary storage area for various received data, and stores various setting data. The operation unit 412 includes an operation panel 102 composed of a touch-inputtable display or the like, and performs various settings by the user and notifies the remaining ink amount information. For image processing that requires high-speed data processing, it is processed by the image processing unit 405, which is a dedicated processing unit. The image processing unit 405 performs image processing on the image data to be recorded by the printing apparatus 100. It converts the color space of the image data input from the host apparatus 400 into a standard RGB color space. Also, various image processes such as resolution conversion, image analysis, and image correction are performed on the image data as necessary. Recording data is generated so that it can be recorded by the print unit 107 through these image processes, and the recording data is stored in the RAM 403.

[0023] In response to a recording instruction from the CPU 401, the head control unit 406 reads out the recording data stored in the RAM 403. The head control unit 406 generates a discharge signal based on the recording data, and the recording element (energy generating element) of the print head 105 is driven by the discharge signal. When the recording element is driven and ink is discharged, an image is formed on the recording medium.

[0024] The engine control unit 407 controls the conveyance mechanism, paper feeding, and paper discharging units within the printing device. Based on instructions from the CPU 401, the engine control unit 407 controls the operations of each unit. The carriage control unit 409 reciprocates the carriage in the main scanning direction in response to an instruction from the CPU 401 regarding the carriage scanning speed. An image is formed on the recording medium by this operation. The air blowing control unit 410 performs air blowing control of the air blowing mechanism unit 120 based on an instruction from the CPU 401 regarding the carriage scanning speed. By this air blowing control, air is blown from the air outlet of the air blowing mechanism unit 120. The recovery control unit 411 controls wiping operations and the like by the wiping mechanism 72 of the recovery unit 70 as recovery operations. The interface 404 is a unit for communicably connecting the control unit 10 and the host device 400, and is a local or network interface.

[0025] The above components are connected by the system bus 408. The host device 400 is a device that supplies image data for causing the printing device 100 to perform recording. The host device 400 may be a general-purpose or dedicated computer, or may be a dedicated image device such as an image capture having an image reader unit, a digital camera, a photo storage, etc. When the host device 400 is a computer, an OS, application software for generating image data, and a printer driver for a printing device or the like are installed in the storage device included in the computer. Note that all of the above processes may be realized by software, or part or all of them may be realized by hardware.

[0026] (Flowchart) FIG. 6 is a flowchart showing the flow of processing using the input image data and various information, together with the components that perform each process.

[0027] The image data 501 in the host device 400 is input to the image processing unit 405. The data conversion process 503 performed within the image processing unit 405 converts the image data 501, which is multi-valued data such as RGB, into binary recording data indicating the ejection or non-ejection of ink droplets from the recording head for each pixel. If the size of the ejected ink droplets is variable, multi-valued data may also be used.

[0028] The binary data is stored in the RAM 403, and when recording is performed, the head control unit 406 reads the recording data from the RAM 403. Based on the read recording data, the head control unit 406 generates an ejection signal in the ejection signal generation 504 and outputs it to the recording head. The recording elements of the print head 105 are driven by the ejection signal, and ink is ejected.

[0029] The count process 505 is a process for obtaining application amount information regarding the amount of ink applied. In this process, based on the binary recording data read from the RAM 403, the number of ink droplets (number of ejections) ejected onto one page (predetermined area) of the recording medium is counted. When the print head 105 can eject large droplets with a large ejection amount and small droplets with a small ejection amount, different coefficients may be multiplied by the number of ejections depending on the size of the ink droplets for counting. In this embodiment, in the case of monochrome, only K is counted, and in the case of color, the total number of ink droplets of KCMY is counted.

[0030] The mode is not limited to monochrome / color, and may be a mode of performing recording only with CMY or a mode of performing recording with two colors, etc. Hereinafter, the number of ink droplets ejected onto one counted page is also referred to as dot count. The recording density (application amount information) is calculated from the counted dot count.

[0031] The head control unit 406 generates a discharge signal in the discharge signal generation 504 based on the recording data read from the RAM 403 and the recording speed determined in the speed determination process 507, and drives the print unit 107. The carriage control unit 409 drives the carriage motor based on an instruction of the carriage scanning speed from the CPU 401. By driving the carriage drive motor, the carriage reciprocates in the main scanning direction, and an image is formed on the recording medium. The air blowing control unit 410 drives the fan 123 of the air blowing duct 109 based on an instruction of the carriage scanning speed from the CPU 401. The fan 123 can be rotated, stopped, and the rotation speed can be changed by electric control. By driving the fan 123 of the air blowing duct 109, air is blown from the air outlet 109a of the air blowing mechanism unit 200.

[0032] (Recording head) FIG. 7 is a schematic diagram showing a planar configuration of the print head 105. The print head 105 of the present embodiment is configured to be able to discharge colored inks such as black, cyan, magenta, and yellow as a liquid for recording, and a reaction ink as a reaction liquid for reacting and aggregating the colored ink.

[0033] The print head 105 is provided with a plurality of discharge port column groups as a plurality of nozzle column groups. That is, a discharge port column group 20R for discharging the reaction ink, a discharge port column group 30K for discharging black ink, a discharge port column group 32C for discharging cyan ink, a discharge port column group 34M for discharging magenta ink, and a discharge port column group 36Y for discharging yellow ink.

[0034] The ejection ports (nozzles) forming these ejection port arrays open to the face surface of the print head 105 facing the sheet conveyance area, and the ejection ports arranged at a predetermined interval in the sheet conveyance direction (X direction) form arrays. Here, the array of reaction ink ejection ports corresponding to the first nozzles corresponds to the first nozzle array, and the array of colored ink ejection ports corresponding to the second nozzles corresponds to the second nozzle array. These arrays of ejection ports are arranged at a predetermined interval in the moving direction (Y direction) of the carriage to form a group. As described above, this ejection port array group is formed corresponding to each of the colored inks of each color as the second nozzle array group and the reaction ink as the first nozzle array group.

[0035] In the ejection port array group 20R of the reaction liquid ink, two even columns (20a, 21a) and two odd columns (20b, 21b) are arranged, and the even columns and the odd columns are arranged so as not to overlap when projected in the Y direction. Also, the nozzle pitch d2 of the even columns is arranged parallel to the X direction at a density of 600 dpi, and the odd columns are similarly arranged at a density of 600 dpi. Furthermore, by shifting the even columns and the odd columns by 600 dpi in the X direction and arranging them in parallel, it is possible to arrange dots on the paper surface at a resolution of d1 (= 1200 dpi).

[0036] Also, the ejection port array groups 30K, 32C, 34M, 36Y of the colored ink have the same nozzle configuration as the ejection port array group 20R, and two even columns and two odd columns are arranged respectively. Here, the nozzle length L1 is, for example, 27 mm, and the distance between the ejection port array group 20R of the reaction liquid ink and the ejection port array group 30K of the black ink is, for example, 86 mm. As described above, by the reaction of the colored ink and the reaction ink on the recording medium, it is possible to suppress feathering and improve the image fastness. However, on the other hand, there is a problem of a decrease in the reliability and life of the recording head due to reaction adhesion on the face surface of the recording head caused by the mist of the colored ink and the reaction ink.

[0037] (Blower mechanism) In this embodiment, the magnitude of the air current by the blower mechanism unit 120 is controlled according to the scanning speed of the carriage 106. This is based on the following idea.

[0038] As shown in FIG. 8, when the carriage 106 moves in the Y direction in the figure at a scanning speed V, an air current (inflow air current) flows between the print head 105 and the sheet 101 as the carriage 106 moves. The magnitude of this inflow air current becomes a wind speed that is approximately equal to the scanning speed V of the carriage 106 (hereinafter referred to as the carriage scanning air current V). At this time, the reactive ink mist 200 flows parallel to the carriage scanning air current V. That is, the reactive ink mist 200 passes directly below the colored ink nozzle, and there is a risk of reactive fixation of the reactive ink and the colored ink on the face surface of the print head 105.

[0039] Therefore, as shown in FIG. 9, an air current S flowing in the sheet conveyance direction with a magnitude (wind speed) sufficiently larger than the magnitude of the carriage scanning air current V accompanying carriage scanning is generated by the blower mechanism unit 120. This air current S acts to move the reactive ink mist 200 generated by the discharge of the reactive liquid in the discharge port row group 20R as the second nozzle row group in the sheet conveyance direction. Thereby, it is possible to avoid the reactive ink mist 200 passing directly below the colored ink nozzle row group as the first nozzle row group.

[0040] On the other hand, as shown in FIG. 10, when the magnitude of the air current S by the blower mechanism unit 120 is small with respect to the magnitude of the carriage scanning air current V, the reactive ink mist 200 passes directly below the colored ink, and reactive fixation cannot be completely avoided.

[0041] In FIGS. 9 and 10, an example in which the reaction ink mist passes directly below the colored ink nozzle was shown, but the same applies when the colored ink mist passes directly below the reaction ink nozzle. That is, it is a case where the nozzle row group of the colored ink becomes the second nozzle row group and the nozzle row group of the reaction liquid becomes the first nozzle row group. In other words, in any case where the carriage 106 scans in the forward and return directions, it is necessary to control the wind speed by the blower mechanism unit 120.

[0042] Also, when the magnitude (wind speed) of the air flow S by the blower mechanism unit 120 is too large, it will affect the landing state of the ejected ink. This is shown in FIG. 11. FIG. 11 is an image diagram of the landing state when ink is ejected from all of the above-described nozzle rows. As shown in FIG. 11(a), when the dot landing state is an ideal state, the dots are neatly arranged at intervals of the dot resolution d2 (1200 dpi) in the X direction. On the other hand, as shown in FIGS. 11(b) and 11(c), as the wind speed increases, the landing position is washed away in the blowing direction, and the landing shape deteriorates, leading to image quality deterioration such as image unevenness. Therefore, it is desirable that the magnitude (wind speed) of the air flow S by the blower mechanism unit 120 be the minimum necessary with respect to the carriage scanning air flow V.

[0043] (Blowing control method) A specific blowing control method will be described with reference to FIG. 12. In FIG. 12, the colored ink and the discharge port row group (30K, 32C, 34M, 36Y) to be discharged are defined as the first discharge port row group, and the discharge port row group 20R for discharging the reaction ink is defined as the second discharge port row group.

[0044] Here, let the nozzle length in the conveyance direction of the first and second discharge port row groups be L1 (hereinafter referred to as the nozzle row length L1). L1 is defined as the distance between the outermost nozzles that perform discharge during the recording operation in the conveyance direction (X direction) of the nozzle rows of the first and second discharge port row groups.

[0045] Also, let the distance in the direction intersecting the conveyance direction of the first discharge port column group and the second discharge port column group be W1 (hereinafter referred to as the distance W1 between discharge port column groups). Further, W1 is defined as the distance between the leftmost nozzle column with discharge during the recording operation in the first discharge port column group and the rightmost nozzle column with discharge during the recording operation in the second discharge port column group (the distance between column 30a of the 30K column group and column 21b of the 20R column group in FIG. 12).

[0046] Furthermore, let the speed at which the carriage 106 moves be V (hereinafter referred to as the carriage movement speed V), and let the scanning airflow generated by the movement of the carriage 106 be V (hereinafter referred to as the carriage scanning airflow V). This embodiment is characterized in that the magnitude (wind speed) of the airflow S (hereinafter referred to as the air blowing S) by the blower mechanism unit 120 is determined based on these nozzle column lengths L1, the distance W1 between discharge port column groups, and the carriage movement speed V. As described above, the carriage movement speed V ≒ the carriage scanning airflow V is described.

[0047] As shown in FIG. 12, the inclination of the flow of the reaction ink mist 200 should be such that it can avoid the opposing position of the first discharge port row group on the upstream side in the moving direction of the carriage 106 with respect to the second discharge port row group. The inclination can be defined by the positional relationship between the most upstream end nozzle 210 of the rightmost nozzle row 21b (the second nozzle row) of the second discharge port row group in the conveyance direction and the most downstream end nozzle 310 of the leftmost nozzle row 30a (the first nozzle row) of the first discharge port row group in the conveyance direction. That is, if an inclination of the flow of the reaction ink mist 200 can be formed such that the mist generated at the most upstream end nozzle 210 does not pass directly below the most downstream end nozzle 310, then inevitably, the mist generated at other nozzles will not pass directly below the nozzles of the first discharge port row group. That is, the inclination of the flow of the mist 200 may be approximately the same as the inclination of the line segment 201 connecting the most upstream end nozzle 210 (the second nozzle) of the rightmost nozzle row 21b (the second nozzle row) and the most downstream end nozzle 310 (the first nozzle) of the leftmost nozzle row 30a (the first nozzle row). Hereinafter, it is referred to as the inclination 201 connecting the most upstream end nozzles. This inclination can be realized by giving an airflow S with a magnitude (wind speed) corresponding to the carriage scanning airflow V in the sheet conveyance direction (X direction). Thereby, it is possible to expect the effect that most of the reaction ink mist 200 flows downstream in the air blowing direction without passing directly below the first discharge port row group of the colored ink.

[0048] The inclination 201 connecting the most upstream end nozzles can be obtained from the nozzle row length L1 and the distance W1 between the discharge port row groups. In the present embodiment, the rightmost nozzle row 21b (the second nozzle row) and the leftmost nozzle row 30a (the first nozzle row) are in substantially the same position in the sheet conveyance direction and are in a positional relationship of facing each other parallel to each other in the moving direction of the carriage 106. Therefore, ultimately, the nozzle row length L1 is synonymous with the distance between the most upstream end nozzle 210 (the second nozzle) and the most downstream end nozzle 310 (the first nozzle) in the positional relationship in the sheet conveyance direction. Also, the distance W1 between the discharge port row groups is ultimately synonymous with the distance between the most upstream end nozzle 210 (the second nozzle) and the most downstream end nozzle 310 (the first nozzle) in the positional relationship in the moving direction of the carriage 106.

[0049] Figure 13 shows a case where the nozzle row length L1 is the same as that in Figure 12, but the distance W2 between the ejection port row groups is larger than W1 in Figure 12. At this time, since the inclination 201 connecting the outermost nozzles becomes smaller than that in Figure 12, if the carriage scanning airflow V remains unchanged, the magnitude (wind speed) of the airflow S can be smaller than that in the case of Figure 12. Here, the carriage moving speed V is not always constant and will vary depending on the recording conditions. Here, the magnitude (wind speed) of the airflow S required by the blower mechanism unit 120 is determined by the following calculation formula. Note that 3.12 in the following formula is a coefficient specific to the device and may be appropriately set according to the device specifications.

Equation

[0050] According to this formula, by controlling the magnitude of the airflow S based on the nozzle row length L, the distance W between the ejection port row groups, and the carriage moving speed V, it becomes possible to ensure the landing system without allowing the reaction ink mist 200 to pass through the colored ink row as much as possible. As an example, when the nozzle row length L is 27 mm, the distance W between the ejection port row groups is 86 mm, and the carriage moving speed V is 60 inch / sec, the required wind speed of the airflow S is approximately 1.5 m / sec.

[0051] (Flowchart) Figure 14 shows a flowchart of the air supply control. First, the carriage control unit acquires an instruction of the carriage scanning speed from the CPU (S1). Next, the carriage motor is driven so as to reach the value of the acquired carriage scanning speed (S2). Also, Figure 15(a) shows an example of the carriage speed according to the recording mode. The lower the image quality mode, the faster the carriage moving speed, and in the high image quality mode, the moving speed is relatively slower. When the carriage drive motor is driven, the carriage reciprocates in the main scanning direction and the recording operation starts (S5).

[0052] The air supply control unit determines the magnitude (wind speed) of the airflow S required in the air supply mechanism unit based on the obtained carriage scanning speed according to the above relational expression (S3). Then, immediately after starting the recording operation, the fan of the air supply duct is driven so as to reach the determined wind speed value (S4). The air supply fan can be rotated, stopped, and its rotation speed changed by electric control. By driving the fan of the air supply duct, air supply is performed from the air outlet of the air supply mechanism unit (S4). Then, air supply is performed from the air supply duct at the start of recording. When there is a next page after the end of recording (S6), the carriage scanning speed during recording is acquired again. When there is no next page, the carriage scanning drive and air supply are turned off (S8, S9).

[0053] In addition, the above control performs the same control in the forward path direction and the return path direction, and the same effect can be obtained in either direction. Also, in the acceleration / deceleration region, control is performed with the airflow S at the same wind speed as in the constant speed region (recording region).

[0054] The control of the airflow S in this embodiment is such that the larger the carriage scanning speed, the larger the magnitude of the airflow S. A specific control example is shown in FIG. 15(b). Another specific example of the control of the magnitude of the airflow S according to the difference in the recording mode is shown in FIG. 15(c). Although specific examples are omitted, the magnitude of the airflow S may be controlled according to the type of the recording medium.

[0055] Furthermore, control may be performed such that the magnitude of the airflow S is different when the carriage scans in one direction (the first direction) and when it scans in the other direction (the second direction opposite to the first direction) during the reciprocating scan. For example, when the amount of colored ink mist generation is small and the influence of reaction fixation is small, in the scanning direction in which the colored ink ejection port array group is downstream in the moving direction of the carriage with respect to the reaction ink ejection port array group, the magnitude of the airflow S may be made smaller than during scanning in the reverse direction.

[0056] With the above configuration and control, it is possible to improve the reliability and extend the life of the recording head without sacrificing water resistance and feathering, and furthermore, it is possible to provide an inkjet recording apparatus with excellent landing accuracy.

[0057] (Embodiment 2) Embodiment 2 of the present invention will be described with reference to FIGS. 16 and 17. FIGS. 16 and 17 are an example in which a plurality of discharge port row groups are arranged in a staggered pattern. In this embodiment, as a plurality of recording heads, there are provided a print head 105a having a discharge port row group 20R for discharging reaction liquid ink, and print heads 105b having discharge port row groups 30K, 32C, 34M, and 36Y for discharging colored ink, respectively. Further, in this embodiment, the two print heads 105a and 105b are arranged in parallel in a staggered pattern in which their positional relationships in the X direction are shifted from each other.

[0058] Regarding the configurations common to Embodiment 1 in Embodiment 2, the same reference numerals are given and the description is omitted. Matters not particularly described here in Embodiment 2 are the same as in Embodiment 1.

[0059] This embodiment is characterized in that, as in Embodiment 1, the magnitude (wind speed) of the air flow S by the blower mechanism unit 120 is determined based on the nozzle row length L, the distance W between the discharge port row groups, and the carriage movement speed V. Note that, as described above, the nozzle row length L is defined as the distance between the outermost nozzles that perform discharge during the recording operation in the conveyance direction (X direction) of the nozzle rows of the first and second discharge shoe row groups. The nozzle row length L in this embodiment is the distance between the outermost nozzles of the first and second discharge port row groups (between the nozzle most downstream in the X direction of the first discharge port row group and the nozzle most upstream in the X direction of the second discharge port row group).

[0060] Comparing Embodiment 1 and this embodiment, in the example of FIG. 16, the distance W1 between the discharge port row groups is the same as in Embodiment 1, but the nozzle row length L2 is larger in this embodiment, and the inclination 201 connecting the outermost nozzles is larger than in Embodiment 1. Therefore, it is necessary to increase the magnitude (wind speed) of the air flow S by the blower mechanism unit 120.

[0061] On the other hand, in FIG. 17, an example is shown where the nozzle row length L2 is the same as that in FIG. 16, but the distance W2 between the discharge port row groups is larger. In this case, since the inclination 201 connecting the outermost nozzles is smaller than that in FIG. 16, the magnitude (wind speed) of the air flow S by the blower mechanism 120 can be made smaller. That is, also in the configuration as in the present embodiment, based on the nozzle row length L, the distance W between the discharge port row groups, and the carriage scanning speed V, the magnitude (wind speed) of the air flow S by the blower mechanism 120 is controlled. By doing so, even in the case of a head with a long nozzle row length L or a head configuration in which a plurality of heads are arranged in a staggered pattern, reaction fixing can be suppressed with the minimum necessary wind speed of the air flow S. Regarding the flowchart, since it is the same as that in the first embodiment, a detailed description is omitted.

[0062] With the above configuration and control, it is possible to improve the reliability and increase the lifespan of the recording head without sacrificing water resistance and feathering, and furthermore, it is possible to provide an inkjet recording apparatus excellent in the landing system.

[0063] (Embodiment 3) Embodiment 3 of the present invention is a modification of Embodiment 1. For the configurations common to Embodiment 1 in Embodiment 3, the same reference numerals are given and the description is omitted. Matters not particularly described here in Embodiment 3 are the same as those in Embodiment 1.

[0064] In the present embodiment, a print head 105c having a nozzle configuration as shown in FIG. 18 is used. That is, on the recording medium, the nozzle row of the reaction ink is longer on the upstream side in the recording medium conveyance direction than the nozzle row of the colored ink so that the reaction ink always lands before the colored ink lands. By this, feathering and the like can be more reliably suppressed.

[0065] In the case of a recording head as shown in FIG. 18, it is desirable to change the magnitude of the air flow by the blower mechanism 57 when the carriage scans in the first direction and when it scans in the second direction opposite to the first direction. As shown in FIGS. 19(a) and 19(b), the minimum required magnitude of the air flow by the blower mechanism unit 120 for suppressing reaction fixing is different when scanning in the first direction and when scanning in the second direction opposite to the first direction. The control of the blower mechanism unit 120 in the present embodiment is shown in FIG. 20. Even when using a recording head in which the nozzle row of the reaction ink is longer on the upstream side in the conveyance direction than the nozzle row of the colored ink as in the present embodiment, by controlling the magnitude of the air flow by the blower mechanism according to the carriage scanning speed and the recording mode, the same effects as in Embodiment 1 can be obtained. That is, it is possible to provide an inkjet recording apparatus that can improve the reliability of the recording head, extend its life, and ensure landing accuracy without sacrificing water resistance and feathering.

[0066] (Embodiment 4) Embodiment 4 of the present invention is an application example of Embodiment 1. For the components common to Embodiment 1 in Embodiment 4, the same reference numerals are given and the description is omitted. Matters not particularly described here in Embodiment 4 are the same as in Embodiment 1.

[0067] In the present embodiment, recovery control is performed according to the magnitude of the air flow by the blower mechanism unit 120, specifically, the preliminary discharge amount during recording is controlled. The preliminary discharge during recording is performed every two scans into the preliminary discharge receiver 71 in the recovery unit 70. In the present embodiment, the preliminary discharge amount per time is controlled according to the magnitude of the air flow by the blower mechanism 120. This is shown in FIG. 21(a). This is because the greater the magnitude of the air flow by the blower mechanism unit 120, the more the evaporation and thickening of the ink near the surface of the print head 105 are promoted, so the preliminary discharge amount required for recovery increases.

[0068] In this embodiment, although the preliminary ejection amount during recording is controlled, other recovery controls such as the preliminary ejection frequency, wiping frequency, wiping intensity, etc. may also be controlled. The greater the magnitude of the airflow by the blower mechanism unit, the higher the preliminary ejection frequency, the higher the wiping frequency, and the higher the wiping intensity may be set.

[0069] When controlling the preliminary ejection frequency, the preliminary ejection frequency may be controlled according to the magnitude of the airflow by the blower mechanism unit 120. This is shown in Fig. 21(b). When controlling the wiping frequency, the wiping frequency may be controlled according to the magnitude of the airflow by the blower mechanism unit 120. This is shown in Fig. 21(c). When controlling the wiping intensity, the number of wiping times per wipe may be controlled according to the magnitude of the airflow by the blower mechanism 57. This is shown in Fig. 21(d).

[0070] As in this embodiment, by controlling the magnitude of the airflow by the blower mechanism according to the carriage scanning speed and the recording mode, and controlling the recovery control according to the magnitude of the airflow by the blower mechanism unit, the reliability of the recording head and the stability of ejection can be further ensured.

[0071] (Embodiment 5) Embodiment 5 of the present invention is an application example of Embodiment 1. For the configurations common to Embodiment 1 in Embodiment 5, the same reference numerals are given and the description is omitted. Matters not particularly described here in Embodiment 5 are the same as in Embodiment 1.

[0072] In Embodiment 1, the magnitude of the airflow by the blower mechanism unit 120 was controlled according to the carriage speed and the recording mode. In contrast, in this embodiment, during the period between recording scans and the next recording scan, or during a period when ejection by the recording head is not performed, such as between pages, the airflow by the blower mechanism unit is made larger. This is shown in Fig. 22. This is because even if the airflow by the blower mechanism is large during the period when ejection is not performed, there is no landing impact, so that the mist of the colored ink and the reactive ink can be more effectively discharged from the vicinity of the recording head.

[0073] As in this embodiment, by controlling the magnitude of the air flow by the blower mechanism according to the carriage scanning speed and the recording mode, and controlling the air flow to increase during the period when ejection by the recording head is not performed, the reliability of the recording head can be further ensured.

[0074] (Embodiment 6) Embodiment 6 of the present invention is an application example of Embodiment 1. For the configurations common to Embodiment 1 in Embodiment 6, the same reference numerals are given and the description is omitted. Matters not particularly described here in Embodiment 6 are the same as in Embodiment 1.

[0075] In Embodiment 1, the magnitude of the air flow by the blower mechanism unit 120 was controlled according to the carriage speed and the recording mode. On the other hand, in this embodiment, since the size of the recording medium is small, the air flow by the blower mechanism unit is increased in the area where recording scanning is not performed. This is shown in FIG. 23. This is because even if the air flow by the blower mechanism unit is large in the area where recording scanning is not performed, there is no landing impact, and thus the mist of the colored ink and the reactive ink can be more effectively discharged from the vicinity of the recording head. As in this embodiment, by controlling the magnitude of the air flow by the blower mechanism according to the carriage scanning speed and the recording mode, and controlling the air flow to increase in the area where recording scanning is not performed, the reliability of the recording head can be further ensured.

[0076] As in this embodiment, by controlling the magnitude of the air flow by the blower mechanism according to the carriage scanning speed and the recording mode, and controlling the air flow to increase in the area where recording scanning is not performed, the reliability of the recording head can be further ensured.

[0077] (Embodiment 7) Embodiment 7 of the present invention is an application example of Embodiment 1. For the configurations common to Embodiment 1 in Embodiment 7, the same reference numerals are given and the description is omitted. Matters not particularly described here in Embodiment 7 are the same as in Embodiment 1.

[0078] The blower mechanism of Embodiment 7 has a slightly different configuration from that of Embodiment 1, and includes five blower fans 109A, 109B, 109C, 109D, and 109E arranged in the scanning direction of the carriage 106. The airflows generated by the blower fans 109A to 109E are caused to flow through the duct 109F into the space between the print head 105 and the recording medium. Each of the blower fans 109A to 109E is configured to be individually and independently controllable, and it is possible to control the magnitude of the airflow discharged from the duct 109F for each of a plurality of regions divided in the moving direction of the carriage 106.

[0079] In Embodiment 1, the magnitude of the airflow by the blower mechanism was controlled according to the carriage speed and the recording mode. In contrast, in this embodiment, the magnitude of the airflow by the blower fans 109A to 109E is dynamically controlled in conjunction with the carriage position. This is shown in FIG. 24. This is because in the regions and periods where recording scanning is not performed, even if the airflow by the blower mechanism is large, there is no landing impact, so the mist of the colored ink and the reactive ink can be more effectively discharged from the vicinity of the recording head.

[0080] By controlling the magnitude of the airflow by the blower mechanism according to the carriage scanning speed and the recording mode as in this embodiment, and dynamically controlling the magnitude of the airflow in conjunction with the carriage position, the reliability of the recording head can be further ensured.

Explanation of Reference Numerals

[0081] 105: Print head, 106: Carriage, 107: Print unit, 109: Blower duct, 119: Fan unit, 120: Blower mechanism, 123: Fan, 210: Outermost nozzle (second nozzle), 310: Outermost nozzle (first nozzle)

Claims

1. Conveying means for conveying a sheet in the conveying direction, A carriage that performs reciprocating scanning in a crossing direction that intersects the conveying direction, A recording head held by the carriage and having a liquid ejection unit that ejects liquid onto the sheet, A first nozzle provided in the liquid ejection unit so as to face the sheet, A second nozzle provided in the liquid ejection unit so as to face the sheet and located apart from the first nozzle in the crossing direction of the carriage with respect to the first nozzle, Airflow generating means for generating an airflow flowing in the conveying direction between the sheet and the liquid ejection unit, Control means for controlling the magnitude of the airflow generated by the airflow generating means and the moving speed of the carriage, A recording apparatus comprising: The control means: The recording apparatus is characterized in that the control means sets the magnitude of the airflow generated by the airflow generating means based on the moving speed of the carriage and the arrangement of the first nozzle and the second nozzle.

2. The recording apparatus according to claim 1, wherein the magnitude of the airflow generated by the airflow generating means is set based on the distance between the first nozzle and the second nozzle in the moving direction of the carriage and the distance between the first nozzle and the second nozzle in the conveying direction.

3. The airflow is an airflow for moving mist generated by ejection of liquid at the second nozzle in the conveying direction, The recording apparatus according to claim 2, wherein the airflow generating means generates an airflow having a magnitude such that the mist is moved in the conveying direction without passing between the first nozzle and the sheet.

4. One of the first nozzle and the second nozzle is a nozzle for ejecting a recording liquid, and the other is a nozzle for ejecting a reaction liquid that reacts with the recording liquid. The recording apparatus according to claim 2 or 3, characterized in that.

5. Further comprising a first nozzle row composed of a plurality of nozzles arranged in the conveying direction including the first nozzle, and a second nozzle row composed of a plurality of nozzles arranged in the conveying direction including the second nozzle, The first nozzle is the most downstream nozzle in the conveying direction among the plurality of nozzles included in the first nozzle row, The recording apparatus according to any one of claims 2 to 4, wherein the second nozzle is the most upstream nozzle in the conveyance direction among the plurality of nozzles included in the second nozzle row.

6. The recording apparatus further includes: a first nozzle row group including a plurality of nozzle rows arranged in the crossing direction and including the first nozzle row; and a second nozzle row group including a plurality of nozzle rows arranged in the crossing direction and including the second nozzle row. The first nozzle row is the most downstream nozzle row in the moving direction among the plurality of nozzles included in the first nozzle row group. The recording apparatus according to claim 5, wherein the second nozzle row is the most upstream nozzle row in the moving direction among the plurality of nozzles included in the second nozzle row group.

7. The recording apparatus according to any one of claims 2 to 6, wherein the control means controls the magnitude of the airflow generated by the airflow generating means to decrease as the moving speed of the carriage decreases.

8. The recording apparatus according to any one of claims 2 to 7, wherein the control means controls the magnitude of the airflow generated by the airflow generating means to decrease as the distance between the first nozzle and the second nozzle in the moving direction increases.

9. The recording apparatus according to any one of claims 1 to 8, wherein the control means controls the magnitude of the airflow generated by the airflow generating means to decrease as the distance between the first nozzle and the second nozzle in the conveyance direction decreases.

10. The recording apparatus according to claim 6, wherein the positions of the most upstream nozzle in the conveyance direction in the first nozzle row group and the most upstream nozzle in the conveyance direction in the second nozzle row group are different in the conveyance direction.

11. The recording apparatus further includes a recovery means for performing a recovery operation of the recording head, including removing the liquid attached to the liquid discharge portion and removing residues in the nozzle. The recording apparatus according to any one of claims 1 to 10, wherein the control means controls the recovery operation by the recovery means based on the magnitude of the airflow generated by the airflow generating means.

12. The recovery operation includes a preliminary discharge operation of causing the liquid discharge portion to discharge liquid to remove residues in the nozzle. The recording apparatus according to claim 11, wherein the control means increases the amount of liquid discharged in the preliminary discharge operation as the magnitude of the airflow generated by the airflow generating means increases.

13. The recording apparatus according to claim 12, wherein the control means increases the frequency of the preliminary discharge operation as the magnitude of the airflow generated by the airflow generating means increases.

14. The recovery means includes wiping means for wiping the liquid discharge portion, The recording apparatus according to any one of claims 11 to 13, wherein the control means increases the frequency of wiping by the wiping means as the magnitude of the airflow generated by the airflow generating means increases.

15. The recording apparatus according to claim 14, wherein the control means increases the intensity of wiping by the wiping means as the magnitude of the airflow generated by the airflow generating means increases.

16. The recording apparatus according to any one of claims 1 to 15, wherein the control means controls so that the magnitude of the airflow generated by the airflow generating means increases while the liquid discharge portion is not discharging liquid.

17. The recording apparatus according to any one of claims 1 to 16, wherein the control means controls so that the magnitude of the airflow generated by the airflow generating means increases when the liquid discharge portion is not in a position facing the sheet during a recording operation of recording on the sheet.

18. The control means is capable of controlling the magnitude of the airflow generated by the airflow generating means for each of a plurality of regions divided in the moving direction of the carriage, The recording apparatus according to any one of claims 1 to 16, wherein the magnitude of the airflow in a region where the liquid discharge portion is not located is controlled to be larger than the magnitude of the airflow in a region where the liquid discharge portion is located among the plurality of regions.

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